Committed at 6cec7b06b3c8187b36fc05cfd4dd38b42313d727
Thanks,
Di
> -----Original Message-----
> From: Richard Biener <richard.guent...@gmail.com>
> Sent: Friday, December 22, 2023 11:40 PM
> To: Di Zhao OS <diz...@os.amperecomputing.com>
> Cc: Thomas Schwinge <tho...@codesourcery.com>; gcc-patches@gcc.gnu.org
> Subject: Re: [PATCH v4] [tree-optimization/110279] Consider FMA in
> get_reassociation_width
>
>
>
> > Am 22.12.2023 um 16:05 schrieb Di Zhao OS <diz...@os.amperecomputing.com>:
> >
> > Updated the fix in attachment.
> >
> > Is it OK for trunk?
>
> Ok
>
> > Tested on aarch64-unknown-linux-gnu and x86_64-pc-linux-gnu.
> >
> > Thanks,
> > Di Zhao
> >
> >> -----Original Message-----
> >> From: Di Zhao OS <diz...@os.amperecomputing.com>
> >> Sent: Sunday, December 17, 2023 8:31 PM
> >> To: Thomas Schwinge <tho...@codesourcery.com>; gcc-patches@gcc.gnu.org
> >> Cc: Richard Biener <richard.guent...@gmail.com>
> >> Subject: RE: [PATCH v4] [tree-optimization/110279] Consider FMA in
> >> get_reassociation_width
> >>
> >> Hello Thomas,
> >>
> >>> -----Original Message-----
> >>> From: Thomas Schwinge <tho...@codesourcery.com>
> >>> Sent: Friday, December 15, 2023 5:46 PM
> >>> To: Di Zhao OS <diz...@os.amperecomputing.com>; gcc-patches@gcc.gnu.org
> >>> Cc: Richard Biener <richard.guent...@gmail.com>
> >>> Subject: RE: [PATCH v4] [tree-optimization/110279] Consider FMA in
> >>> get_reassociation_width
> >>>
> >>> Hi!
> >>>
> >>> On 2023-12-13T08:14:28+0000, Di Zhao OS <diz...@os.amperecomputing.com>
> >> wrote:
> >>>> --- /dev/null
> >>>> +++ b/gcc/testsuite/gcc.dg/pr110279-2.c
> >>>> @@ -0,0 +1,41 @@
> >>>> +/* PR tree-optimization/110279 */
> >>>> +/* { dg-do compile } */
> >>>> +/* { dg-options "-Ofast --param tree-reassoc-width=4 --param fully-
> >>> pipelined-fma=1 -fdump-tree-reassoc2-details -fdump-tree-optimized" } */
> >>>> +/* { dg-additional-options "-march=armv8.2-a" { target aarch64-*-* } }
> */
> >>>> +
> >>>> +#define LOOP_COUNT 800000000
> >>>> +typedef double data_e;
> >>>> +
> >>>> +#include <stdio.h>
> >>>> +
> >>>> +__attribute_noinline__ data_e
> >>>> +foo (data_e in)
> >>>
> >>> Pushed to master branch commit 91e9e8faea4086b3b8aef2355fc12c1559d425f6
> >>> "Fix 'gcc.dg/pr110279-2.c' syntax error due to '__attribute_noinline__'",
> >>> see attached.
> >>>
> >>> However:
> >>>
> >>>> +{
> >>>> + data_e a1, a2, a3, a4;
> >>>> + data_e tmp, result = 0;
> >>>> + a1 = in + 0.1;
> >>>> + a2 = in * 0.1;
> >>>> + a3 = in + 0.01;
> >>>> + a4 = in * 0.59;
> >>>> +
> >>>> + data_e result2 = 0;
> >>>> +
> >>>> + for (int ic = 0; ic < LOOP_COUNT; ic++)
> >>>> + {
> >>>> + /* Test that a complete FMA chain with length=4 is not broken. */
> >>>> + tmp = a1 + a2 * a2 + a3 * a3 + a4 * a4 ;
> >>>> + result += tmp - ic;
> >>>> + result2 = result2 / 2 - tmp;
> >>>> +
> >>>> + a1 += 0.91;
> >>>> + a2 += 0.1;
> >>>> + a3 -= 0.01;
> >>>> + a4 -= 0.89;
> >>>> +
> >>>> + }
> >>>> +
> >>>> + return result + result2;
> >>>> +}
> >>>> +
> >>>> +/* { dg-final { scan-tree-dump-not "was chosen for reassociation"
> >>> "reassoc2"} } */
> >>>> +/* { dg-final { scan-tree-dump-times {\.FMA } 3 "optimized"} } */
> >>
> >> Thank you for the fix.
> >>
> >>> ..., I still see these latter two tree dump scans FAIL, for GCN:
> >>>
> >>> $ grep -C2 'was chosen for reassociation' pr110279-2.c.197t.reassoc2
> >>> 2 *: a3_40
> >>> 2 *: a2_39
> >>> Width = 4 was chosen for reassociation
> >>> Transforming _15 = powmult_1 + powmult_3;
> >>> into _63 = powmult_1 + a1_38;
> >>> $ grep -F .FMA pr110279-2.c.265t.optimized
> >>> _63 = .FMA (a2_39, a2_39, a1_38);
> >>> _64 = .FMA (a3_40, a3_40, powmult_5);
> >>>
> >>> ..., nvptx:
> >>>
> >>> $ grep -C2 'was chosen for reassociation' pr110279-2.c.197t.reassoc2
> >>> 2 *: a3_40
> >>> 2 *: a2_39
> >>> Width = 4 was chosen for reassociation
> >>> Transforming _15 = powmult_1 + powmult_3;
> >>> into _63 = powmult_1 + a1_38;
> >>> $ grep -F .FMA pr110279-2.c.265t.optimized
> >>> _63 = .FMA (a2_39, a2_39, a1_38);
> >>> _64 = .FMA (a3_40, a3_40, powmult_5);
> >>
> >> For these 2 targets, the reassoc_width for FMUL is 1 (default value),
> >> While the testcase assumes that to be 4. The bug was introduced when I
> >> updated the patch but forgot to update the testcase.
> >>
> >>> ..., but also x86_64-pc-linux-gnu:
> >>>
> >>> $ grep -C2 'was chosen for reassociation' pr110279-2.c.197t.reassoc2
> >>> 2 *: a3_40
> >>> 2 *: a2_39
> >>> Width = 2 was chosen for reassociation
> >>> Transforming _15 = powmult_1 + powmult_3;
> >>> into _63 = powmult_1 + powmult_3;
> >>> $ grep -cF .FMA pr110279-2.c.265t.optimized
> >>> 0
> >>
> >> For x86_64 this needs "-mfma". Sorry the compile options missed that.
> >> Can the change below fix these issues? I moved them into
> >> testsuite/gcc.target/aarch64, since they rely on tunings.
> >>
> >> Tested on aarch64-unknown-linux-gnu.
> >>
> >>>
> >>> Grüße
> >>> Thomas
> >>>
> >>>
> >>> -----------------
> >>> Siemens Electronic Design Automation GmbH; Anschrift: Arnulfstraße 201,
> >> 80634
> >>> München; Gesellschaft mit beschränkter Haftung; Geschäftsführer: Thomas
> >>> Heurung, Frank Thürauf; Sitz der Gesellschaft: München; Registergericht
> >>> München, HRB 106955
> >>
> >> Thanks,
> >> Di Zhao
> >>
> >> ---
> >> gcc/testsuite/{gcc.dg => gcc.target/aarch64}/pr110279-1.c | 3 +--
> >> gcc/testsuite/{gcc.dg => gcc.target/aarch64}/pr110279-2.c | 3 +--
> >> 2 files changed, 2 insertions(+), 4 deletions(-)
> >> rename gcc/testsuite/{gcc.dg => gcc.target/aarch64}/pr110279-1.c (83%)
> >> rename gcc/testsuite/{gcc.dg => gcc.target/aarch64}/pr110279-2.c (78%)
> >>
> >> diff --git a/gcc/testsuite/gcc.dg/pr110279-1.c
> >> b/gcc/testsuite/gcc.target/aarch64/pr110279-1.c
> >> similarity index 83%
> >> rename from gcc/testsuite/gcc.dg/pr110279-1.c
> >> rename to gcc/testsuite/gcc.target/aarch64/pr110279-1.c
> >> index f25b6aec967..97d693f56a5 100644
> >> --- a/gcc/testsuite/gcc.dg/pr110279-1.c
> >> +++ b/gcc/testsuite/gcc.target/aarch64/pr110279-1.c
> >> @@ -1,6 +1,5 @@
> >> /* { dg-do compile } */
> >> -/* { dg-options "-Ofast --param avoid-fma-max-bits=512 --param tree-
> reassoc-
> >> width=4 -fdump-tree-widening_mul-details" } */
> >> -/* { dg-additional-options "-march=armv8.2-a" { target aarch64-*-* } } */
> >> +/* { dg-options "-Ofast -mcpu=generic --param avoid-fma-max-bits=512 --
> param
> >> tree-reassoc-width=4 -fdump-tree-widening_mul-details" } */
> >>
> >> #define LOOP_COUNT 800000000
> >> typedef double data_e;
> >> diff --git a/gcc/testsuite/gcc.dg/pr110279-2.c
> >> b/gcc/testsuite/gcc.target/aarch64/pr110279-2.c
> >> similarity index 78%
> >> rename from gcc/testsuite/gcc.dg/pr110279-2.c
> >> rename to gcc/testsuite/gcc.target/aarch64/pr110279-2.c
> >> index b6b69969c6b..a88cb361fdc 100644
> >> --- a/gcc/testsuite/gcc.dg/pr110279-2.c
> >> +++ b/gcc/testsuite/gcc.target/aarch64/pr110279-2.c
> >> @@ -1,7 +1,6 @@
> >> /* PR tree-optimization/110279 */
> >> /* { dg-do compile } */
> >> -/* { dg-options "-Ofast --param tree-reassoc-width=4 --param fully-
> pipelined-
> >> fma=1 -fdump-tree-reassoc2-details -fdump-tree-optimized" } */
> >> -/* { dg-additional-options "-march=armv8.2-a" { target aarch64-*-* } } */
> >> +/* { dg-options "-Ofast -mcpu=generic --param tree-reassoc-width=4 --param
> >> fully-pipelined-fma=1 -fdump-tree-reassoc2-details -fdump-tree-optimized" }
> */
> >>
> >> #define LOOP_COUNT 800000000
> >> typedef double data_e;
> >> --
> >> 2.25.1
> > <0001-Fix-compile-options-of-pr110279-1.c-and-pr110279-2.c.patch>
